You would be better off with a high definition still camera on a stand.

Many of the point and click cameras can be set to take black and white images that are greyscale.

They also can be teathered to the computer so you can control the camera from the pc, send the image directly to the pc, and even use photoshop to convert the images to bistable B&W images not greyscale. Withe use of a weighted bar to hold the page open you can minimize the curvature error of the image at the binding.

You can set the system up so it is faster than a scanner.

Research the line of Sony, Makita, Ricoh, or any other pocket 4 to 8
megapixel point and shoot cameras. Many can be controlled by the computer and cost less than the unit you are looking at. Any camera store has camera mounts that could be setup on a fourpoint rack system to allow you to set the camera at any angle. You would be looking at 4 to 5 times the resolution of that dedicated scanner. When you are not using it to scan a book you have yourself a nice little camera to use for other things.